Motor control constant calculation device

ABSTRACT

By providing a configuration for calculating motor control constants to be set in a motor control apparatus automatically on the basis of a target response time constant obtained from a target response time constant input unit, waveform parameters obtained from a waveform parameter input unit, a normalized time constant obtained from a normalized time constant calculation unit, and a motor load inertia obtained from a motor load inertia input unit, it is possible to obtain a motor control constant calculation device that can determine appropriate motor control constants for obtaining a desired response characteristic by automatic calculation while avoiding variation and an increase in the number of steps due to differences in the abilities of users.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No.PCT/JP2014/062664 filed May 13, 2014, the contents of which areincorporated herein by reference in their entirety.

TECHNICAL FIELD

This invention relates to a motor control constant calculation devicethat calculates appropriate motor control constants to be set in a motorcontrol apparatus in order to obtain a desired response characteristic.

BACKGROUND ART

During motor speed control, a control gain must be increased in order toimprove a speed response and a robustness with which speed variationaccompanying load variation is suppressed. However, a motor speed signalobtained from an encoder or a resolver includes noise, and therefore,when the control gain is increased, the noise is amplified, leading to areduction in the stability of the motor speed. Hence, there is a limitto the control performance that can be achieved simply by increasing thecontrol gain.

To avoid this situation, means for reducing the noise included in themotor speed signal by inserting a low pass filter (an LPF) is typicallyemployed. However, when a cutoff frequency of the LPF is reduced inorder to improve the noise reduction effect, a phase of the motor speedsignal is retarded such that the speed response deteriorates.

To improve the control performance, therefore, appropriate motor controlconstants to be set in a motor control apparatus must be determined inconsideration of the tradeoff between the control gain and the cutofffrequency of the LPF.

Here, a method of determining motor control constants through automaticcalculation simply by applying a single parameter defining a desiredresponse speed, thereby ensuring that the motor control constants arenot determined by trial and error due to the tradeoff described above,has been proposed in the prior art (see PTL 1, for example).

More specifically, in the conventional technique described in PTL 1, themotor control constants are determined automatically by applying atarget response frequency ω_(f) as the parameter defining the desiredresponse speed. Note that the motor control constants serving as thesubject of this conventional technique include a position loop gain of aposition control unit of the motor control apparatus, a speed loop gainand a speed integration time constant of a speed control unit, a filterconstant of a torque filter unit, a current loop gain and a currentintegration time constant of a current control unit, and a filter timeconstant of a speed signal creation unit (in other words, an LPF).

Further, in PTL 1, a speed control loop is considered as a secondarysystem represented only by the speed loop gain and a motor load inertia,and the speed loop gain is determined so that a characteristic equationof a transfer function having a range that extends from a target speed(a speed command) to the motor speed (an actual speed) has a repeatedroot. Furthermore, a calculation expression for determining the filtertime constant is defined by trial and error on the basis of a stabilitycondition of a control system and a repeatedly performed experiment.

CITATION LIST Patent Literature

[PTL 1]

Japanese Patent Publication No. 3561911

SUMMARY OF INVENTION Technical Problem

However, the prior art includes the following problems. In theconventional technique described in PTL 1, the speed loop gain isdetermined without taking into consideration the LPF that reduces thenoise included in the motor speed signal. Therefore, when the LPF iseventually inserted and the motor is controlled using the determinedspeed loop gain, the speed response actually deteriorates relative tothe target response frequency ω_(f) applied during the determinationoperation. In other words, the determined speed loop gain cannot alwaysbe considered as an appropriate motor control constant.

Further, in the conventional technique described in PTL 1, thecalculation expression for determining the filter time constant isdefined by trial and error. As a result, depending on the abilities of auser (an operator), optimum motor control constants may vary and anumber of steps required to determine an appropriate filter timeconstant may increase.

This invention has been designed to solve the problems described above,and an object thereof is to obtain a motor control constant calculationdevice that can determine appropriate motor control constants forobtaining a desired response characteristic by automatic calculationwhile avoiding variation and an increase in the number of steps due todifferences in the abilities of users.

Solution to Problem

A motor control constant calculation device according to this inventioncalculates motor control constants for a motor control apparatus so thata motor obtains a desired response characteristic, the motor controlapparatus having a target speed command generation unit that generates atarget speed as a speed command relating to the motor, a first LPF thatimplements filtering processing on a signal waveform of the target speedinput from the target speed command generation unit, a second LPF thatreduces noise in a signal waveform of a motor speed detected from themotor, a speed deviation calculation unit that calculates a deviationbetween the target speed and the motor speed after the target speed andthe motor speed pass through the first LPF and the second LPF,respectively, a target motor torque calculation unit that calculates atarget torque to be generated by the motor on the basis of thedeviation, and an applied motor voltage calculation unit that calculatesa voltage to be applied to the motor on the basis of the target torque,and outputs the calculated voltage to the motor, wherein the motorcontrol constant calculation device includes a target response timeconstant input unit used to input and set a target response timeconstant defining a response speed so that the desired responsecharacteristic is obtained, a waveform parameter input unit used toinput and set waveform parameters defining a response waveform so thatthe desired response characteristic is obtained, a motor load inertiainput unit used to input and set a motor load inertia of the motor, anormalized time constant calculation unit that calculates a normalizedtime constant on the basis of the waveform parameters obtained from thewaveform parameter input unit, and a motor control constant calculationunit that calculates a filter time constant, a proportional gain, and anintegral gain as motor control constants to be set in relation to thefirst LPF, the second LPF, and the target motor torque calculation uniton the basis of the target response time constant obtained from thetarget response time constant input unit, the waveform parametersobtained from the waveform parameter input unit, the normalized timeconstant obtained from the normalized time constant calculation unit,and the motor load inertia obtained from the motor load inertia inputunit.

Advantageous Effects of Invention

According to this invention, a configuration is provided for calculatingthe motor control constants to be set in the motor control apparatusautomatically on the basis of the target response time constant obtainedfrom the target response time constant input unit, the waveformparameters obtained from the waveform parameter input unit, thenormalized time constant obtained from the normalized time constantcalculation unit, and the motor load inertia obtained from the motorload inertia input unit. As a result, it is possible to obtain a motorcontrol constant calculation device that can determine appropriate motorcontrol constants for obtaining a desired response characteristic byautomatic calculation while avoiding variation and an increase in thenumber of steps due to differences in the abilities of users.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram showing an overall configuration of a motorcontrol system including a motor control constant calculation deviceaccording to a first embodiment of this invention.

FIG. 2 is a block diagram showing a configuration of a motor controlconstant calculation device according to a second embodiment of thisinvention.

FIG. 3 is a block diagram showing a configuration of a motor controlconstant calculation device according to a third embodiment of thisinvention.

FIG. 4 is a block diagram showing a configuration of a motor controlconstant calculation device according to a fourth embodiment of thisinvention.

FIG. 5 is an illustrative view showing an example of a response waveformdisplayed by a normalized waveform display unit of the motor controlconstant calculation device according to the fourth embodiment of thisinvention.

FIG. 6 is a block diagram showing a configuration of a motor controlconstant calculation device according to a fifth embodiment of thisinvention.

FIG. 7 is a block diagram showing a configuration of a motor controlsystem including a motor control constant calculation device accordingto a sixth embodiment of this invention.

DESCRIPTION OF EMBODIMENTS

Preferred embodiments of a motor control constant calculation deviceaccording to this invention will be described below using the drawings.Note that in the drawings, identical reference numerals have beenallocated to identical elements, and duplicate description thereof hasbeen omitted.

First Embodiment

FIG. 1 is a block diagram showing an overall configuration of a motorcontrol system including a motor control constant calculation device 200according to a first embodiment of this invention.

In FIG. 1, the motor control system includes a motor 10, a detector 20that is connected to the motor 10 in order to obtain a motor speedsignal from the motor 10, a motor control apparatus 100 that controlsdriving of the motor 10, and the motor control constant calculationdevice 200 that calculates optimum motor control constants to be set inthe motor control apparatus 100.

The motor control apparatus 100 includes a target speed commandgeneration unit 101, a first LPF 102, a speed deviation calculation unit103, a target motor torque calculation unit 104, an applied motorvoltage calculation unit 105, a second LPF 106, a motor control constantstorage unit 107, and a first communication I/F 108.

The target speed command generation unit 101 generates a target speedω_(ref) as a speed command relating to the motor 10, and outputs thegenerated target speed ω_(ref) to the speed deviation calculation unit103 via the first LPF 102. Hence, the target speed ω_(ref) is input intothe speed deviation calculation unit 103 after passing through the firstLPF 102, in which a signal waveform thereof is subjected to filterprocessing in accordance with a filter time constant. Note thathereafter, the target speed ω_(ref) after passing through the first LPF102 will be denoted specifically as a target speed ω_(ref)′.

Here, a transfer function F_(ref)(s) of the first LPF 102 is expressedby Equation (A) shown below, for example, using a proportional gainK_(vp), an integral gain K_(vi), and a time constant (the filter timeconstant) τ_(LPF) of the first LPF 102.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 1} \right\rbrack & \; \\{{F_{ref}(s)} = \frac{K_{vi}}{\left( {{K_{vp}s} + K_{vi}} \right)\left( {{\tau_{LPF}s} + 1} \right)}} & (A)\end{matrix}$

The detector 20 detects a position of the motor 10 and outputs a motorspeed ω (an actual speed) of the motor 10 as a motor speed signal on thebasis of the detection result. Further, the motor speed ω output fromthe detector 20 is input into the speed deviation calculation unit 103via the second LPF 106. Hence, the motor speed ω is input into the speeddeviation calculation unit 103 after passing through the second LPF, inwhich noise is removed from a signal waveform thereof. Note thathereafter, the motor speed ω after passing through the second LPF 106will be denoted specifically as a motor speed ω′. The motor speed ωoutput by the detector 20 is therefore input into the second LPF 106 andfed back to the speed deviation calculation unit 103 in the form of themotor speed ω′.

Here, a transfer function F_(LPF)(s) of the second LPF 106 is expressedby Equation (B) shown below, for example, using the time constant (thefilter time constant) τ_(LPF) of the second LPF 106.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 2} \right\rbrack & \; \\{{F_{LPF}(s)} = \frac{1}{{\tau_{LPF}s} + 1}} & (B)\end{matrix}$

The speed deviation calculation unit 103 calculates a deviation betweenthe target speed ω_(ref)′ and the motor speed ω′ input therein, or inother words a speed deviation e_(ω) (=ω_(ref)′−ω′), and outputs thecalculated speed deviation e_(ω) to the target motor torque calculationunit 104.

The target motor torque calculation unit 104 calculates a target torqueT_(ref) of the motor 10 using the input speed deviation e_(ω). Further,the target motor torque calculation unit 104 outputs the calculatedtarget torque T_(ref) to the applied motor voltage calculation unit 105.

Here, a transfer function C_(FB)(s) of the target motor torquecalculation unit 104 is expressed by Equation (C) shown below, forexample, using the proportional gain K_(vp) and the integral gainK_(vi).

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 3} \right\rbrack & \; \\{{C_{FB}(s)} = {K_{vp} + \frac{K_{vi}}{s}}} & (C)\end{matrix}$

The applied motor voltage calculation unit 105 calculates a voltage tobe applied to the motor 10 so that a torque T generated by the motor 10follows the input target torque T_(ref), and outputs the calculatedvoltage to the motor 10.

The proportional gain K_(vp), the integral gain K_(vi), and the filtertime constant τ_(LPF) are stored in the motor control constant storageunit 107 as appropriate motor control constants calculated automaticallyby the motor control constant calculation device 200 in order to obtaina desired response characteristic.

The first LPF 102, the target motor torque calculation unit 104, and thesecond LPF 106 obtain the motor control constants stored in the motorcontrol constant storage unit 107. As a result, the appropriate motorcontrol constants calculated automatically by the motor control constantcalculation device 200 are set in the first LPF 102, the target motortorque calculation unit 104, and the second LPF 106.

The motor control constant calculation device 200 includes a targetresponse time constant input unit 201, a motor control constantcalculation unit 202, a waveform parameter input unit 203, a normalizedtime constant calculation unit 204, a motor control constant displayunit 205, a motor load inertia input unit 206, and a secondcommunication I/F 207. Further, the motor control constant calculationunit 202 includes a filter time constant calculation unit 202 a and aspeed control constant calculation unit 202 b.

The target response time constant input unit 201 is used to input andset a target response time constant τ_(d) defining a response speed sothat the motor 10 exhibits the desired response characteristic. Further,the waveform parameter input unit 203 is used to input and set waveformparameters γ₁, γ₂ defining a response waveform so that the motor 10exhibits the desired response characteristic.

Furthermore, the motor load inertia input unit 206 is used to input andset a motor load inertia J corresponding to a load characteristic of themotor 10. By providing the target response time constant input unit 201,the waveform parameter input unit 203, and the motor load inertia inputunit 206, a user can set the target response time constant τ_(d), thewaveform parameters γ₁, γ₂, and the motor load inertia J freely, asdesired, in the motor control constant calculation unit 202.

The normalized time constant calculation unit 204 calculates anormalized time constant τ_(s) on the basis of the waveform parametersγ₁, γ₂ obtained from the waveform parameter input unit 203, and outputsthe calculated normalized time constant τ_(s) to the motor controlconstant calculation unit 202. A method of calculating the normalizedtime constant τ_(s) will now be described. In the motor controlapparatus 100, a transfer function G(s) from the target speed ω_(ref) tothe motor speed ω is as shown in a following equation.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 4} \right\rbrack & \; \\{{G(s)} = \frac{K_{vi}}{{{J\tau}_{LPF}s^{3}} + {Js}^{2} + {K_{vp}s} + K_{vi}}} & \;\end{matrix}$

Further, the waveform parameters γ₁, γ₂ and τ_(e) are defined byfollowing equations.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 5} \right\rbrack & \; \\{\gamma_{1} = {{\frac{K_{vp}^{2}}{{JK}_{vi}}\mspace{31mu}\gamma_{2}} = {{\frac{J}{\tau_{LPF}K_{vp}}\mspace{25mu}\tau_{e}} = {\frac{K_{vp}}{K_{vi}} = {\tau_{LPF}\gamma_{1}\gamma_{2}}}}}} & \;\end{matrix}$

Using these equations, the transfer function G(s) can be rewritten as afollowing equation.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 6} \right\rbrack \\{{G(s)} = \frac{1}{{\frac{1}{\gamma_{2}\gamma_{1}^{2}}\left( {\tau_{e}s} \right)^{3}} + {\frac{1}{\gamma_{1}}\left( {\tau_{e}s} \right)^{2}} + {\tau_{e}s} + 1}}\end{matrix}$

Hence, τ_(e)s may be taken as a new variable such that the transferfunction G(s) is considered as G(τ_(e)s). A response waveform of thetransfer function G(τ_(e)s) is determined by a coefficient of adenominator polynomial, and the determined response waveform isdetermined univocally in accordance with values of the waveformparameters γ₁, γ₂. Further, a scale of a time direction of the responsewaveform is dependent on the variable τ_(e)s, and therefore the responsespeed is determined from τ_(e). On the basis of the above, a transferfunction obtained by replacing the variable τ_(e)s with s′ andnormalizing a temporal axis by τ_(e) is set as G_(n)(s′), and a valueobtained by calculating a time constant of a step response of thetransfer function G_(n)(s′) is set as the normalized time constantτ_(s). Note that the normalized time constant τ_(s) corresponds to acombination of the waveform parameters γ₁, γ₂ at a ratio of 1 to 1.

The transfer function G_(n)(s′) is expressed by Equation (D), shownbelow, using the waveform parameters γ₁, γ₂.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 7} \right\rbrack & \; \\{{G_{n}\left( s^{\prime} \right)} = \frac{1}{{\frac{1}{\gamma_{2}\gamma_{1}^{2}}{s^{\prime}}^{3}} + {\frac{1}{\gamma_{1}}{s^{\prime}}^{2}} + s^{\prime} + 1}} & (D)\end{matrix}$

The motor control constant calculation unit 202 calculates theproportional gain K_(vp), the integral gain K_(vi), and the filter timeconstant τ_(LPF) as the motor control constants to be set in the motorcontrol apparatus 100, and outputs the calculated motor controlconstants to the motor control apparatus 100. As is evident from therespective transfer functions expressed above in Equations (A) to (C),the first embodiment illustrates a case in which the proportional gainK_(vp), the integral gain K_(vi), and the filter time constant τ_(LPF)to be set in the first LPF 102, the time constant τ_(LPF) to be set inthe second LPF 106, and the proportional gain K_(vp) and integral gainK_(vi) to be set in the target motor torque calculation unit 104 arecalculated.

The filter time constant calculation unit 202 a calculates the filtertime constant τ_(LPF) on the basis of the target response time constantτ_(d) obtained from the target response time constant input unit 201,the waveform parameters γ₁, γ₂ obtained from the waveform parameterinput unit 203, and the normalized time constant τ_(s) obtained from thenormalized time constant calculation unit 204 so as to satisfy Equation(E), shown below.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 8} \right\rbrack & \; \\{\tau_{LPF} \leq \frac{\tau_{d}}{\tau_{s}\gamma_{1}\gamma_{2}}} & (E)\end{matrix}$

A method of calculating Equation (E) will now be described. A timeconstant of the transfer function G(s) expressing a real-time responsewith respect to the normalized time constant τ_(s) is τ_(e)τ_(s).Accordingly, a condition applied to the filter time constant τ_(LPF) inorder to realize the target response time constant τ_(d) is as shown ina following equation.τ_(d)≧τ_(e)τ_(s)=τ_(LPF)γ₁γ₂τ_(s)  [Math. 9]

By modifying the above expression, Equation (E) is obtained.

Further, on the basis of the calculated filter time constant τ_(LPF),the filter time constant calculation unit 202 a calculates a cutofffrequency f_(LPF) as a further motor control constant in accordance withEquation (F), shown below.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 10} \right\rbrack & \; \\{f_{LPF} = \frac{1}{2{\pi\tau}_{LPF}}} & (F)\end{matrix}$

The speed control constant calculation unit 202 b calculates theproportional gain K_(vp) and the integral gain K_(vi) on the basis ofthe waveform parameters γ₁, γ₂ obtained from the waveform parameterinput unit 203, the motor load inertia J obtained from the motor loadinertia input unit 206, and the filter time constant τ_(LPF) obtainedfrom the filter time constant calculation unit 202 a in accordance withEquations (G) and (H), shown below.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 11} \right\rbrack & \; \\{K_{vp} = \frac{J}{\tau_{LPF}\gamma_{2}}} & (G) \\{K_{vi} = {\frac{K_{vp}^{2}}{J\;\gamma_{1}} = \frac{J}{\tau_{LPF}^{2}\gamma_{1}\gamma_{2}^{2}}}} & (H)\end{matrix}$

The proportional gain K_(vp), the integral gain K_(vi), and the filtertime constant τ_(LPF) calculated by the motor control constantcalculation unit 202 in this manner are input into the motor controlconstant storage unit 107 via the second communication I/F 207 and thefirst communication I/F 108. As a result, the motor control constantscalculated automatically by the motor control constant calculation unit202 are set in the first LPF 102, the target motor torque calculationunit 104, and the second LPF 106 by the motor control constant storageunit 107.

The motor control constant display unit 205 displays the motor controlconstants calculated by the motor control constant calculation unit 202.As a result, the user can confirm specific numerical values of the motorcontrol constants calculated by the motor control constant calculationunit 202 immediately by sight.

According to the first embodiment, as described above, the motor controlconstants to be set in the motor control apparatus are calculatedautomatically on the basis of the target response time constant obtainedfrom the target response time constant input unit, the waveformparameters obtained from the waveform parameter input unit, thenormalized time constant obtained from the normalized time constantcalculation unit, and the motor load inertia obtained from the motorload inertia input unit.

In addition, stability in the transfer function G(s) is guaranteedlogically by establishing γ₁≧1.5 and γ₂≧1.5. As a rule of thumb, afavorable response waveform is obtained in terms of fluctuation andovershoot by establishing γ₁=2.5 and γ₂=2. The response waveform, incontrast to the response speed, is typically somewhat limited in termsof a desired shape regardless of the aim of the motor speed control, andtherefore the user preferably sets values in the vicinity of γ₁=2.5 andγ₂=2 in the waveform parameter input unit 203 in advance as defaultvalues. Further, when the motor load inertia J is fixed, the fixed motorload inertia J is preferably set in the motor load inertia input unit206 in advance as a default value. According to this invention, theresponse speed and the response waveform can be adjusted independentlyin accordance with the target response time constant τ_(d) and thewaveform parameters γ₁, γ₂, respectively, and therefore, by setting thewaveform parameters γ₁, γ₂ and the motor load inertia J at the defaultvalues, the user can obtain motor control constants for realizing thedesired response characteristic simply by applying the target responsetime constant τ_(d).

Hence, appropriate motor control constants for obtaining a desiredresponse characteristic can be determined by automatic calculation whileavoiding variation and an increase in the number of steps due todifferences in the abilities of users. Moreover, even inexperiencedusers can set appropriate motor control constants in the motor controlapparatus easily, without trial and error. As a result, variation in thecontrol performance due to differences in the abilities of users can beprevented, and a number of development steps required for a settingoperation can be greatly reduced.

Note that when the cutoff frequency f_(LPF) is calculated in accordancewith Equation (F) on the basis of the filter time constant τ_(LPF),which is calculated such that Equation (E) holds, (in other words, whenf_(LPF)=τ_(s)γ₁γ₂/2πτ_(d)), a following effect is obtained.

The cutoff frequency f_(LPF) of the second LPF 106 logically reaches aminimum when the response characteristic of the motor 10 is within arange where the target response time constant τ_(d) can be achieved.Therefore, a motor speed control system with which noise can beminimized while achieving the desired response characteristic isobtained.

Second Embodiment

The motor control constant calculation device 200 according to a secondembodiment of this invention differs from the motor control constantcalculation device 200 according to the first embodiment (FIG. 1) asfollows. The motor control constant calculation device 200 according tothe second embodiment is configured similarly to the motor controlconstant calculation device 200 according to the first embodiment, butfurther includes a ramp response specification input unit 208. Thefollowing description focuses on this difference.

FIG. 2 is a block diagram showing a configuration of the motor controlconstant calculation device 200 according to the second embodiment ofthis invention.

The ramp response specification input unit 208 is used to input and seta target acceleration a_(ref) of a ramp response and an allowable valuee_(ramp) of an absolute value e_(ss) of a steady state deviation of theramp response from the target acceleration as ramp responsespecifications so that the motor 10 exhibits a desired ramp responsecharacteristic. By further including the ramp response specificationinput unit 208, the user can set desired ramp response specificationsfreely in the motor control constant calculation unit 202 in addition tothe desired target response time constant τ_(d), waveform parameters γ₁,γ₂, and motor load inertia J. As a result, appropriate motor controlconstants for obtaining the desired response characteristic can bedetermined by automatic calculation while additionally taking intoconsideration the ramp response specifications.

In other words, the filter time constant calculation unit 202 acalculates the filter time constant τ_(LPF) on the basis of the targetresponse time constant τ_(d) obtained from the target response timeconstant input unit 201, the waveform parameters γ₁, γ₂ obtained fromthe waveform parameter input unit 203, the normalized time constantτ_(s) obtained from the normalized time constant calculation unit 204,and the target acceleration a_(ref) and the allowable value e_(ramp)obtained from the ramp response specification input unit 208 so as tosatisfy Equation (I), shown below.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 12} \right\rbrack & \; \\{\tau_{LPF} \leq {\min\left( {\frac{\tau_{d}}{\tau_{s}\gamma_{1}\gamma_{2}},\frac{e_{ramp}}{{a_{ref}}\gamma_{1}\gamma_{2}}} \right)}} & (I)\end{matrix}$

To describe the right side of Equation (I) further, the sign min(τ_(d)/τ_(s)γ₁γ₂, e_(ramp)/|a_(ref)|γ₁γ₂) means that the respectivevalues of τ_(d)/τ_(s)γ₁γ₂ and e_(ramp)/|a_(ref)|γ₁γ₂ are compared, andthe smaller thereof is taken.

A method of calculating Equation (I) is as follows. In the transferfunction G(s) from the target speed ω_(ref) to the motor speed ω, theabsolute value e_(ss) of the steady state deviation of the ramp responsewhen the target acceleration is set at a_(ref) is as shown by afollowing equation.e _(ss) =|a _(ref)|τ_(LPF)γ₁γ₂  [Math. 13]

A condition that is applied to the filter time constant τ_(LPF) in orderto suppress the absolute value e_(ss) of the steady state deviation ofthe ramp response to or below the allowable value e_(ramp) is obtainedfrom the above equation, and by combining this condition with theconditional expression (E) relating to the target response time constantτ_(d), Equation (I) is obtained.

The filter time constant calculation unit 202 a calculates the cutofffrequency f_(LPF) in accordance with Equation (F) on the basis of thefilter time constant τ_(LPF) calculated as described above.

Further, the speed control constant calculation unit 202 b calculatesthe proportional gain K_(vp) and the integral gain K_(vi) in accordancewith Equations (G) and (H) on the basis of the filter time constantτ_(LPF) calculated as described above. Hence, in the second embodiment,appropriate motor control constants can be calculated taking intoconsideration both the target response speed and the ramp responsespecifications.

According to the second embodiment, as described above, the rampresponse specification input unit, which is used to input and set thetarget acceleration of the ramp response and the allowable value of thesteady state deviation from the target acceleration as ramp responsespecifications enabling the motor to realize a desired ramp responsecharacteristic, is provided in addition to the first embodiment, andtherefore a configuration for calculating the motor control constants onthe basis of the ramp response specifications obtained from the rampresponse specification input unit is provided.

As a result, appropriate motor control constants calculated inconsideration of both the target response speed and the ramp responsespecifications can be set in the motor control apparatus.

Note that when the cutoff frequency f_(LPF) is calculated in accordancewith Equation (F) on the basis of the filter time constant τ_(LPF),which is calculated such that Equation (I) holds, a following effect isobtained.

The cutoff frequency f_(LPF) of the second LPF 106 logically reaches aminimum when the response characteristic of the motor 10 is within arange set in consideration of both the target response time constantτ_(d) and the allowable value e_(ramp) of the absolute value e_(ss) ofthe steady state deviation of the ramp response from the targetacceleration. Therefore, a motor speed control system with which noisecan be minimized while taking into consideration the desired speedcharacteristic and the ramp response specifications as the desiredresponse characteristic is obtained.

Third Embodiment

The motor control constant calculation device 200 according to a thirdembodiment of this invention differs from the motor control constantcalculation device 200 according to the first embodiment (FIG. 1) asfollows. In comparison with the control constant calculation device 200according to the first embodiment, the motor control constantcalculation device 200 according to the third embodiment includes afilter time constant input unit 209 in place of the target response timeconstant input unit 201, and includes a target response time constantcalculation unit 202 c in place of the filter time constant calculationunit 202 a. The following description focuses on these differences.

FIG. 3 is a block diagram showing a configuration of the motor controlconstant calculation device 200 according to the third embodiment ofthis invention. Further, since the ramp response specifications of thesecond embodiment are not set, the target response time constant τ_(d)and the filter time constant τ_(LPF) have a 1 to 1 relationship, as isevident from Equation (E). Accordingly, the motor control constantcalculation device 200 can be configured as shown in FIG. 3.

The filter time constant input unit 209 is used to input and set thefilter time constant τ_(LPF) so that the motor 10 exhibits the desiredresponse characteristic. By providing the filter time constant inputunit 209 in place of the target response time constant input unit 201 inthis manner, the user can set the desired filter time constant τ_(LPF)freely in the motor control constant calculation unit 202.

The target response time constant calculation unit 202 c calculates thetarget response time constant τ_(d) on the basis of the filter timeconstant τ_(LPF) obtained from the filter time constant input unit 209,the waveform parameters γ₁, γ₂ obtained from the waveform parameterinput unit 203, and the time constant τ_(s) obtained from the normalizedtime constant calculation unit 204 so as to satisfy Equation (J), shownbelow.[Math. 14]τ_(d)≧τ_(LPF)τ_(s)γ₁γ₂  (J)

Further, the speed control constant calculation unit 202 b calculatesthe proportional gain K_(vp) and the integral gain K_(vi) in accordancewith Equations (G) and (H) on the basis of the filter time constantτ_(LPF) obtained from the filter time constant input unit 209.

According to the third embodiment, as described above, a configurationfor calculating the motor control constants to be set in the motorcontrol apparatus automatically on the basis of the filter time constantobtained from the filter time constant input unit, the waveformparameters obtained from the waveform parameter input unit, thenormalized time constant obtained from the normalized time constantcalculation unit, and the motor load inertia obtained from the motorload inertia input unit is provided in addition to the first embodiment.

Hence, the filter time constant τ_(LPF) can be input and set so as toprioritize noise reduction, and as a result, similar effects to thefirst embodiment can be obtained.

Note that when τ_(d) is calculated such that Equation (J) holds (inother words, when τ_(d)=τ_(LPF) τ_(s) γ₁ γ₂), a following effect isobtained.

The target response time constant τ_(d) logically reaches a minimumwithin a range that is achievable when the filter time constant τ_(LPF)obtained from the filter time constant input unit 209 is set as the timeconstant of the second LPF 106. The third embodiment is thereforeeffective in a case where the motor control constants are set so as toprioritize noise reduction over the response speed.

For example, when the motor is used as a propulsion device for avehicle, a resolver is typically employed as a motor rotation angledetector. However, a pulse (a resolver pulse) that is synchronous withthe motor rotation angle may be superimposed on the resolver output dueto an attachment error in the resolver or an electric circuitcharacteristic. Further, the resolver pulse is generated at a frequencythat is synchronous with the motor rotation angle. Therefore, byinputting and setting the filter time constant τ_(LPF) in the filtertime constant input unit 209 in consideration of this frequency, theeffect of the pulse can be reduced preferentially, and as a result, amotor speed control system exhibiting the fastest achievable speedresponse can be obtained.

Fourth Embodiment

The motor control constant calculation device 200 according to a fourthembodiment of this invention differs from the motor control constantcalculation device 200 according to the first embodiment (FIG. 1) asfollows. The motor control constant calculation device 200 according tothe fourth embodiment is configured similarly to the motor controlconstant calculation device 200 according to the first embodiment, butfurther includes a normalized waveform display unit 210. The followingdescription focuses on this difference.

FIG. 4 is a block diagram showing a configuration of the motor controlconstant calculation device 200 according to the fourth embodiment ofthis invention.

According to this invention, the response speed and the responsewaveform can be adjusted independently in accordance with the targetresponse time constant τ_(d) and the waveform parameters γ₁, γ₂,respectively.

Therefore, by varying the waveform parameters γ₁, γ₂ input and set inthe waveform parameter input unit 203, a degree of fluctuation and adegree of overshoot in the step response can be set independently whilecontinuing to satisfy the target response speed.

The normalized waveform display unit 210 displays a response waveformrelating to G_(n)(s′), which is obtained by normalizing the temporalaxis of the transfer function G(s) from the target speed ω_(ref) to themotor speed ω by τ_(e), on the basis of the waveform parameters γ₁, γ₂obtained from the waveform parameter input unit 203.

As a result, the user can select the waveform parameters γ₁, γ₂ forrealizing the desired response waveform visually by checking the displayon the normalized waveform display unit 210 while varying the waveformparameters γ₁, γ₂ input and set in the waveform parameter input unit203. Moreover, since the waveform parameters γ₁, γ₂ can be selectedvisually in this manner, the degree of fluctuation and the degree ofovershoot can be adjusted easily while continuing to satisfy the desiredresponse characteristics (the target response speed and the rampresponse specifications).

Here, an example of a response waveform displayed by the normalizedwaveform display unit 210 will be described with reference to FIG. 5.FIG. 5 is an illustrative view showing an example of a response waveformdisplayed by the normalized waveform display unit 210 of the motorcontrol constant calculation device 200 according to the fourthembodiment of this invention. Note that as a specific example of aresponse waveform relating to the transfer function G_(n)(s′), FIG. 5shows a response waveform of the step response of the transfer function.

FIG. 5(a) shows respective response waveforms displayed in a case wherethe user inputs the waveform parameters γ₁, γ₂ into the waveformparameter input unit 203 so as to vary the waveform parameter γ₁ whilekeeping the waveform parameter γ₂ fixed at γ₂=2. Further, FIG. 5(b)shows an enlargement of the vicinity of target values in the responsewaveforms shown in FIG. 5(a).

According to the fourth embodiment, as described above, the normalizedwaveform display unit for displaying a response waveform relating to thetransfer function G_(n)(s′) on the basis of the waveform parametersobtained from the waveform parameter input unit is provided in additionto the configurations of the first to third embodiments.

As a result, the waveform parameters can be selected visually whilechecking the display on the normalized waveform display unit, and thedegrees of fluctuation and overshoot occurring during speed control canbe adjusted easily regardless of the real-time response speed.

Fifth Embodiment

The motor control constant calculation device 200 according to a fifthembodiment of this invention differs from the motor control constantcalculation device 200 according to the first embodiment (FIG. 1) asfollows. The motor control constant calculation device 200 according tothe fifth embodiment is configured similarly to the motor controlconstant calculation device 200 according to the first embodiment, butfurther includes a response waveform display unit 211 and a numericalanalysis condition input unit 212. The following description focuses onthis difference.

FIG. 6 is a block diagram showing a configuration of the motor controlconstant calculation device 200 according to the fifth embodiment ofthis invention.

The response waveform display unit 211 executes numerical analysis undernumerical analysis conditions input into the numerical analysiscondition input unit 212 using the motor control constants calculated bythe motor control constant calculation unit 202 and the motor loadinertia J obtained from the motor load inertia input unit 206, anddisplays the response waveform of the motor 10 in the form of asimulation result.

The numerical analysis condition input unit 212 is used to input and setanalysis conditions. By providing the numerical analysis condition inputunit 212, the user can set desired numerical analysis conditions freelyin the response waveform display unit 211.

Note that an initial speed and a target speed of the step response, aninitial speed, a target speed, and a target acceleration of the rampresponse, a target speed of a constant speed response, and an amplitude,a phase, and a frequency of the noise superimposed on the motor speedsignal, for example, are input as the numerical analysis conditions.

Hence, the response waveform display unit 211 displays a simulationresult obtained by executing numerical analysis. As a result, the usercan immediately confirm by numerical analysis whether or not it will bepossible to achieve the desired control performance when the motorcontrol constants calculated by the motor control constant calculationunit 202 are set in the motor control apparatus 100.

Here, the response waveform display unit 211 may be used in thefollowing form, for example. Specifically, when the motor is used as apropulsion device for a vehicle, a resolver is typically employed as amotor rotation angle detector.

However, a pulse that is synchronous with the motor rotation angle maybe superimposed on the resolver output due to an attachment error in theresolver or an electric circuit characteristic. Further, a resolveroutput signal is converted into a speed signal by differentiation andused during the speed control, but due to the effect of the pulsesuperimposed on the speed signal, a torque command output to the motorfluctuates. As a result, variation occurs in the motor speed, and themagnitude of the variation is dependent on the motor control constantsset in the motor control apparatus 100.

Hence, by inputting the amplitude, phase, and frequency of the resolverpulse into the numerical analysis condition input unit 212 as noise andchecking the control performance from the display on the responsewaveform display unit 211, a prior inspection can be performed on themotor 10 immediately under conditions resembling an actual environment,and as a result, the number of development steps can be reduced.

According to the fifth embodiment, as described above, the numericalanalysis condition input unit used to input and set the numericalanalysis conditions, and the response waveform display unit thatexecutes numerical analysis under the numerical analysis conditionsobtained from the numerical analysis condition input unit using themotor control constants calculated by the motor control constantcalculation unit and the motor load inertia obtained from the motor loadinertia input unit, and displays the response waveform of the motor, areprovided in addition to the configurations of the first to fourthembodiments.

Accordingly, whether or not the motor is able to achieve the desiredcontrol performance under the numerical analysis conditions input andset in the numerical analysis condition input unit can immediately beverified by sight. As a result, the number of development steps can bereduced.

Sixth Embodiment

The motor control constant calculation device 200 according to a sixthembodiment of this invention differs from the motor control constantcalculation device 200 according to the first embodiment (FIG. 1) asfollows. The motor control constant calculation device 200 according tothe sixth embodiment is configured similarly to the motor controlconstant calculation device 200 according to the first embodiment, butfurther includes a motor load inertia calculation unit 213. Thefollowing description focuses on this difference.

FIG. 7 is a block diagram showing a configuration of a motor controlsystem including the motor control constant calculation device 200according to the sixth embodiment of this invention.

In the sixth embodiment, the detector 20 outputs the motor speed ωobtained from the motor 10 to the motor load inertia calculation unit213 via the first communication I/F 108. Further, the target motortorque calculation unit 104 outputs the calculated target torque T_(ref)to the motor load inertia calculation unit 213 via the firstcommunication I/F 108.

The motor load inertia calculation unit 213 calculates the motor loadinertia J on the basis of the motor speed ω and the target torqueT_(ref), which are obtained via the second communication I/F 207, andoutputs the calculated motor load inertia J to the motor load inertiainput unit 206. Various methods may be employed by the motor loadinertia calculation unit 213 to calculate the motor load inertia J. Forexample, when an angular acceleration obtained by numericallydifferentiating the motor speed ω is set as a, the motor load inertia Jis calculated in accordance with Equation (K), shown below. Note thathereafter, the motor load inertia J calculated by the motor load inertiacalculation unit 213 will be denoted specifically as a motor loadinertia J′.

$\begin{matrix}\left\lbrack {{Math}.\mspace{14mu} 15} \right\rbrack & \; \\{J = \frac{T_{ref}}{a}} & (K)\end{matrix}$

The motor load inertia input unit 206 receives the newly set motor loadinertia J′ from the motor load inertia calculation unit 213, and outputsthe motor load inertia J′ to the motor control constant calculation unit202. Hence, the motor load inertia J input and set previously in themotor load inertia input unit 206 is updated successively such that thenew motor load inertia J′ calculated by the motor load inertiacalculation unit 213 is set therein, whereupon the updated motor loadinertia J′ is output to the motor control constant calculation unit 202.

Further, the motor control constant calculation unit 202 uses the motorload inertia J′ updated by the motor load inertia input unit 206 tocalculate the motor control constants. Hence, when load variation occursin the motor 10, the motor control constant calculation unit 202 cancalculate motor control constants that correspond to the load variation.

Here, when the motor is used as a propulsion device for a vehicle, forexample, variation in a vehicle weight caused by passengers and luggage,variation in road surface friction, the effect of gravity in a downhilldirection when traveling uphill, and so on, for example, may be cited asspecific examples of causes of load variation in the motor 10. With theconfiguration of the sixth embodiment, however, the motor controlconstant calculation unit 202 calculates motor control constants thatcorrespond to the load variation, and therefore speed control can beimplemented on the vehicle on the basis of appropriate motor controlconstants for obtaining the desired response characteristic.

According to the sixth embodiment, as described above, the motor loadinertia calculation unit that calculates the motor load inertia on thebasis of the target speed and the target torque obtained from the motorcontrol apparatus is provided in addition to the configurations of thefirst to fifth embodiments. Furthermore, the motor load inertia inputunit according to the sixth embodiment is configured to update the inputand set motor load inertia successively to the motor load inertiacalculated by the motor load inertia calculation unit, and output theupdated motor load inertia to the motor control constant calculationunit.

Hence, when the motor load inertia varies, motor control constants thatcorrespond to the load variation can be calculated. As a result, bysetting these motor control constants anew in the motor controlapparatus, the motor can be controlled on the basis of appropriate motorcontrol constants for obtaining the desired response characteristic.

Note that in the sixth embodiment, when a value of the motor loadinertia J following variation therein is known in advance by the motorload inertia calculation unit 213, a following configuration may beemployed. Specifically, motor control constants corresponding to aplurality of motor load inertia values J may be calculated in advance,whereupon associations (a table, for example) between the motor loadinertia values J and the motor control constants may be defined inadvance and stored in a storage unit of the motor control constantcalculation unit 202.

In this case, the motor load inertia calculation unit 213 outputs themotor load inertia J corresponding to the motor load variation, which isknown in advance, to the motor load inertia input unit 206 withoutobtaining the motor speed ω and the target torque T_(ref) from the motorcontrol apparatus 100 online and recalculating the motor load inertia J.

With this configuration, the motor control constant calculation unit 202can select appropriate motor control constants corresponding to themotor load variation, which is known in advance, directly from thestorage unit (the associations). In other words, the motor controlconstant calculation unit 202 selects appropriate motor controlconstants corresponding to the motor load inertia J obtained from themotor load inertia input unit 206 directly from the storage unit (theassociations).

Further, by setting the motor control constants selected directly fromthe storage unit in the motor control apparatus 100, the motor 10 can becontrolled on the basis of appropriate motor control constants withoutrecalculating the motor load inertia J and updating the motor loadinertia input unit 206. Furthermore, by setting the motor controlconstants selected directly from the storage unit in the motor controlapparatus 100, the motor 10 can be controlled on the basis ofappropriate motor control constants even in a situation where it isdifficult to update the value of the motor load inertia J with a highdegree of precision due to a disturbance in the motor speed signalcaused by sensor noise, outside disturbances, and so on.

More specifically, in a vehicle that uses the motor 10 as a propulsiondevice, for example, a gear change performed by a transmissionconstitutes motor load variation. Further, speed ratios that can beobtained by the transmission are often known in advance. Therefore,motor control constants corresponding to a plurality of speed ratios maybe calculated in advance and stored in the storage unit of the motorcontrol constant calculation unit 202.

In this case, the motor control constant calculation unit 202 selectsappropriate motor control constants corresponding to the speed ratio,which is known in advance, directly from the storage unit. Hence, evenwhen load variation occurs in response to a gear change, the vehicle canbe caused to travel on the basis of appropriate motor control constantswithout obtaining the motor speed ω and the target torque T_(ref) fromthe motor control apparatus 100 online and recalculating the motor loadinertia J.

The invention claimed is:
 1. A motor control constant calculationapparatus that calculates motor control constants for a motor controlapparatus so that a motor exhibits a desired response characteristic,wherein the motor control apparatus includes a first communicationinterface and is configured to generate a target speed as a speedcommand relating to the motor, control a first low pass filter (LPF) toimplement filtering processing on a signal waveform of the generatedtarget speed, control a second LPF to reduce noise in a signal waveformof a motor speed detected from the motor, calculate a deviation betweenthe target speed and the motor speed after the signal waveform of thetarget speed passes through the first LPF and the signal waveform of themotor speed passes through the second LPF, calculate a target torque tobe generated by the motor on the basis of the calculated deviation,calculate a voltage to be applied to the motor on the basis of thecalculated target torque, and output the calculated voltage to themotor, and wherein the motor control constant calculation apparatus isconfigured to receive an input of a target response time constant andset the target response time constant which defines a response speed forobtaining the desired response characteristic, to receive an input ofwaveform parameters and set the waveform parameters which define aresponse waveform for obtaining the desired response characteristic, toreceive an input of a motor load inertia and set the motor load inertiaof the motor, to calculate a normalized time constant on the basis ofthe set waveform parameters, to calculate the motor control constantsincluding a filter time constant, a proportional gain, and an integralgain to be set in relation to the first LPF, the second LPF, and acalculation of the target torque based on the set target response timeconstant, the set waveform parameters, the normalized time constant, andthe set motor load inertia, and to control a second communicationinterface to send the calculated motor constants to the motor controlapparatus through the first communication interface.
 2. The motorcontrol constant calculation apparatus according to claim 1, wherein themotor control constant calculation apparatus is configured to receive aninput of a target acceleration and set the target acceleration of a rampresponse and an allowable value of a steady state deviation from thetarget acceleration as ramp response specifications so that the motorexhibits a desired ramp response characteristic, and to calculate themotor control constants further based on the ramp responsespecifications.
 3. The motor control constant calculation apparatusaccording to claim 2, wherein, in Equations (O), (P), and (Q),$\begin{matrix}{\tau_{LPF} \leq {\min\left( {\frac{\tau_{d}}{\tau_{s}\gamma_{1}\gamma_{2}},\frac{e_{ramp}}{{a_{ref}}\gamma_{1}\gamma_{2}}} \right)}} & (O) \\{K_{vp} = \frac{J}{\tau_{LPF}\gamma_{2}}} & (P) \\{K_{vi} = {\frac{K_{vp}^{2}}{J\;\gamma_{1}} = \frac{J}{\tau_{LPF}^{2}\gamma_{1}\gamma_{2}^{2}}}} & (Q)\end{matrix}$ the motor control constant calculation apparatuscalculates the filter time constant to satisfy Equation (O), andcalculates the proportional gain and the integral gain to satisfyEquations (P) and (Q), where τ_(LPF) denotes the filter time constant,a_(ref) denotes the target acceleration of the ramp response, e_(ramp)denotes the allowable value of the steady state deviation of the rampresponse from the target acceleration, τ_(d) denotes the target responsetime constant, γ₁, γ₂ denote the waveform parameters, τ_(s) denotes thenormalized time constant, K_(vp) denotes the proportional gain, K_(vi)denotes the integral gain, and J denotes the motor load inertia.
 4. Themotor control constant calculation apparatus according to claim 1,wherein, in Equations (L), (M), and (N), $\begin{matrix}{\tau_{LPF} \leq \frac{\tau_{d}}{\tau_{s}\gamma_{1}\gamma_{2}}} & (L) \\{K_{vp} = \frac{J}{\tau_{LPF}\gamma_{2}}} & (M) \\{K_{vi} = {\frac{K_{vp}^{2}}{J\;\gamma_{1}} = \frac{J}{\tau_{LPF}^{2}\gamma_{1}\gamma_{2}^{2}}}} & (N)\end{matrix}$ the motor control constant calculation apparatuscalculates the filter time constant to satisfy Equation (L), andcalculates the proportional gain and the integral gain to satisfyEquations (M) and (N), where τ_(LPF) denotes the filter time constant,τ_(d) denotes the target response time constant, γ₁, γ₂ denote thewaveform parameters, τ_(s) denotes the normalized time constant, K_(vp)denotes the proportional gain, K_(vi) denotes the integral gain, and Jdenotes the motor load inertia.
 5. The motor control constantcalculation apparatus according to claim 1, further comprising: anormalized waveform display to display, on the basis of the set waveformparameters, a response waveform relating to a transfer function that isobtained by normalizing the transfer function from the target speed tothe motor speed by the normalized time constant.
 6. The motor controlconstant calculation apparatus according to claim 1, further comprising:a response waveform display, wherein the motor control constantcalculation apparatus is configured to receive an input of numericalanalysis conditions and set the numerical analysis conditions, and toexecute numerical analysis under the set numerical analysis conditionsusing the calculated motor control constants and the set motor loadinertia, and the response waveform display displays a response waveformof the motor.
 7. The motor control constant calculation apparatusaccording to claim 1, wherein the motor control constant calculationapparatus is configured to calculate the motor load inertia on the basisof the target speed and the target torque obtained from the motorcontrol apparatus, and to successively update the set motor load inertiawith the calculated motor load inertia.
 8. The motor control constantcalculation apparatus according to claim 1, wherein the motor controlconstant calculation apparatus includes a storage unit, and isconfigured to control the storage unit to store motor control constantscalculated in advance so as to correspond to a plurality of motor loadinertia values, and to select appropriate motor control constantscorresponding to a motor load variation that is known in advancedirectly from the storage unit.
 9. A motor control constant calculationapparatus that calculates motor control constants for a motor controlapparatus so that a motor exhibits a desired response characteristic,wherein the motor control apparatus includes a first communicationinterface and is configured to generate a target speed as a speedcommand relating to the motor, control a first low pass filter (LPF) toimplement filtering processing on a signal waveform of the generatedtarget speed, control a second LPF to reduce noise in a signal waveformof a motor speed detected from the motor, calculate a deviation betweenthe target speed and the motor speed after the signal waveform of thetarget speed passes through the first LPF and the signal waveform of themotor speed passes through the second LPF, calculate a target torque tobe generated by the motor based on the calculated deviation, calculate avoltage to be applied to the motor based on the calculated targettorque, and output the calculated voltage to the motor, and wherein themotor control constant calculation apparatus is configured to receive aninput of a filter time constant and set the filter time constant to beused in the first LPF and the second LPF for obtaining the desiredresponse characteristic, to receive an input of waveform parameters andset the waveform parameters which define a response waveform forobtaining the desired response characteristic, to receive an input of amotor load inertia and set the motor load inertia of the motor, tocalculate a normalized time constant based on the set waveformparameters, to calculate the motor control constants including aproportional gain and an integral gain to be set in relation to thefirst LPF, the second LPF, and a calculation of the target torque on thebasis of the set filter time constant, the set waveform parameters, thenormalized time constant, and the set motor load inertia, and to controla second communication interface to send the calculated motor constantsto the motor control apparatus through the first communicationinterface.
 10. The motor control constant calculation apparatusaccording to claim 9, further comprising: a normalized waveform displayto display, on the basis of the set waveform parameters, a responsewaveform relating to a transfer function that is obtained by normalizingthe transfer function from the target speed to the motor speed by thenormalized time constant.
 11. The motor control constant calculationapparatus according to claim 9, further comprising: a response waveformdisplay, wherein the motor control constant calculation apparatus isconfigured to receive an input of numerical analysis conditions and setthe numerical analysis conditions, and to execute numerical analysisunder the set numerical analysis conditions using the calculated motorcontrol constants and the set motor load inertia, and the responsewaveform display displays a response waveform of the motor.
 12. Themotor control constant calculation apparatus according to claim 9,wherein the motor control constant calculation apparatus is configuredto calculate the motor load inertia based on the motor speed and thetarget torque obtained from the motor control apparatus, and tosuccessively update the set motor load inertia with the calculated motorload inertia.
 13. The motor control constant calculation apparatusaccording to claim 9, wherein the motor control constant calculationapparatus includes a storage unit, and is configured to control thestorage unit to store motor control constants calculated in advance soas to correspond to a plurality of motor load inertia values, and toselect appropriate motor control constants corresponding to a motor loadvariation that is known in advance directly from the storage unit.